In sandwich ELISAs, 100% cross-reactivity with recombinant mouse IL-28A/IFN-lambda 2 and no cross-reactivity with recombinant human (rh) IL-28A or rhIL-29 is observed. Reconstitute at 0.5 mg/mL in sterile PBS. Endoxin level is <0.10 EU per 1 μg of the an